chapter 1

• Computer


  A device that receives input, does processing on that input and then produces the output
• Computer


  • Consists of two main components: hardware and software
• Hardware


  The physical components that make up a computer system
• Hardware


  • External
  • Internal
• External Hardware


  Devices that are external and normally visible to the user
• External Hardware


  • Mouse
  • keyboard
  • monitor
  • printer
  • scanner
• Internal Hardware


  Devices that exist inside the computer and are not normally visible to the user
• Software


  Programs for controlling the operation of a computer system and processing of electronic data
• Software


  • Applications
  • System
• Applications Software


  Programs that provide the services that user requires to solve a task
• System Software


  Programs that provide the services that computer requires to run properly
• System Software

  • Operating System (OS)
  • Device Driver
  • Compiler
  • Linkers
  • Utilities (for example, Anti-virus)
• Central Processing Unit (CPU)

  Hardware that processes instructions entered into the computer in order to produce an output
• Parts of CPU


  • Control Unit
  • Arithmetic Logic Unit (ALU)
• Main Memory


  Internal memory that is directly accessible by the CPU, composed of RAM and ROM